The present invention relates to a method of and to an apparatus for manipulating articles of the tobacco processing industry, especially for manipulating articles which include one or more rod-like components and an adhesive-coated sheet-like component. More particularly, the invention relates to improvements in a method of and in an apparatus for effecting removal of articles of the tobacco processing industry from a predetermined path wherein the artices are advanced at predetermined locations, e.g., toward a processing station where two or more components of each article are connected to each other by draping the adhesive-coated sheet-like component around two or more coaxial rod-like components.
It is well known to advance partially assembled or about-to-be assembled articles of the tobacco processing industry along a predetermined path in such a way that the articles are equidistant from each other during travel toward a processing station. By way of example, many presently used filter tipping machines employ rotary drum-shaped conveyors with fluted peripheral surfaces for the transport of groups of coaxial rod-shaped components (e.g., a filter plug of double unit length between two plain cigarettes of unit length) and partially attached adhesive-coated uniting bands toward a draping or rolling station where the uniting bands of successive articles are convoluted around the respective groups to form filter cigarettes of unit length or multiple unit length. Typical examples of such filter tipping machines are those known as MAX and MAX S (both manufactured by the assignee of the present application).
If the operation of one or more units in a filter tipping machine is unsatisfactory (e.g., if a conveyor which transports components of articles in the just outlined manner is contaminated with adhesive paste so that it can no longer predictably advance the components to the draping station, or if the transfer station or stations between such conveyor and the conveyor or conveyors which deliver components of the articles are clogged with articles or with components of articles), it is necessary to interrupt the advancement of additional untreated or unprocessed articles toward the defective unit or units as well as to remove the components which are already on their way toward the affected unit or units. Since each and every interruption of the operation of a modern high-speed filter tipping or like machine entails enormous losses in output (for example, a modern cigarette maker can turn out up to and in excess of 8000 plain cigarettes per minute), it is desirable and advantageous to eliminate minor causes of malfunction while the machine continues to run so as to eliminate those losses which are due to the making of unsatisfactory articles during starting and/or during deceleration of the machine from its rated speed. Thus, at the very least, the elimination of a minor defect while the machine continues to run reduces the total losses in output to those arising during the interval which is actually needed to eliminate the cause or causes of malfunction.
If the conveyor on which the rod-like components of articles in a filter tipping machine are draped into so-called uniting bands (i.e., into adhesive-coated sheet-like components) requires cleaning, the articles which are in the process of advancing toward the draping station must be diverted from the conveyor so that they cannot reach the draping station while the rolling surface of such conveyor is being relieved of remnants of adhesive and/or other impurities. Commonly owned U.S. Pat. No. 4,237,907 to Pawelko et al. discloses a filter tipping machine wherein rod-shaped articles which advance with the peripheral surface of a drum-shaped conveyor and are held thereon by suction can be released by sealing the suction generating device from the suction ports of the conveyor and/or by admitting blasts of compressed air to thus positively expel the components of articles from the flutes at the periphery of the conveyor. A drawback of such proposal is that, as a rule, the suction generating device is disconnected from all suction ports of the drum-shaped conveyor so that the rod-shaped and other components which were held in the respective flutes of the conveyor are free to leave the conveyor (e.g., under the action of gravity and/or under the action of centrifugal force) at a number of different locations along the periphery of the conveyor. This includes the discrete (still unconnected) components of articles which are about to be formed (e.g., by draping an adhesive-coated uniting band around two or more coaxial rod-shaped components) as well as finished articles which advance beyond the processing or assembling station. The thus released articles can contaminate the machine, especially if they descend onto or are otherwise propelled against moving parts which are likely to break, shred and/or otherwise comminute the articles and their components. The articles, their components and the broken-up parts of the articles and/or components clog the passages between successive conveyors and are likely to cause lengthy and extremely costly interruptions of operation of the entire machine.
Another drawback of heretofore known proposals to remove rod-shaped articles of the tobacco processing industry and/or their components from a particular conveyor in a filter tipping or like machine is that the timing of the start and termination of the interval during which the articles are removed cannot be controlled with a desired degree of accuracy. This entails additional losses during the initial stage of removal of articles and/or components as well as when the removal of a given or approximate number of articles and/or components is being completed. The intervals of time which are available for establishing and terminating the connection between a suction generating device and the suction ports of a drum-shaped conveyor in a modern filter tipping machine are extremely short so that it is very difficult to predictably start and/or terminate the separation of rod-shaped articles and/or their components from the conveyor. Improper timing of the start and/or termination of evacuation of air from the suction ports can give rise to additional disturbances, particularly to accumulations of loose articles and/or their components on as well as in the general area of the conveyor.